10 Transactions of the Society. 



The ductus ejaculatorius, as it may probably be called, is a large, 

 straight tube, running forward and downward in the median line ; it 

 enlarges a little, gradually, before reaching the external genital 

 armature, which it surrounds. The penis (p) is a short, chitinous, 

 pyriform or gourd-shaped organ, situated exteriorly on the ventral 

 surface in the median line, between the coxae of the third pair of legs. 

 It is protected by a chitinous armature (ar) formed of a circular 

 ridge, sufficient of the circle being cut away to admit the broad end of 

 the penis, and of a thinner, but still stout, lamina within the circle. 

 This lamina is also cut away to fit the penis, the distal end and edge 

 of which, however, when the organ is not in use, slip under the edge 

 of the lamina, the whole organ then presents the appearance of a 

 chitinous ring surrounding a thin circular plate with a gourd-shaped 

 opening in it ; the chitin of the penis, when seen through from the 

 side, being much thinner than that of the lamina. This is represented 

 by figs. 10, 12, while fig. 13 shows the intromittent organ withdrawn 

 previous to erection. 



The Female Organs. Figs. 14-18. 



The female reproductive organs consist of a central ovary ; two 

 long, paired oviducts ; an unpaired vagina ; and the vestibule. The 

 organs, as before stated, practically form a ring; and they greatly 

 resemble the corresponding parts in the Orihatidse ; but there is one 

 very marked diJfference, viz. the entire absence of the long, protrusible, 

 and collapsible ovipositor, which forms so conspicuous a feature of 

 the system in that family ; and its replacement to some extent by 

 the vestibule, which, however, is strictly an internal structure. The 

 central ovary (figs. 7-14, ov) is placed in the median line, almost at 

 the posterior end of the body ; it naturally varies in size and form, 

 but it most commonly has the general appearance of a bunch of 

 grapes with the small end the nearer to the posterior margin of the 

 body. This ovary looks as though entirely composed of eggs in an 

 early stage of development ; the eggs are not by any means all the 

 same size, but it seems strange that, in all specimens which I have 

 dissected, the smaller eggs have been clustered round the entrance to 

 the oviducts, while the larger eggs were chiefly at the hinder end 

 and periphery of the ovary ; this would be comprehensible enough if 

 the eggs were placed dehisced into a body-cavity, but this does not 

 appear to be the case ; one is therefore led to suggest that the eggs 

 may possibly work backward along the periphery of the mass, and 

 then forward to the mouth of the oviduct through the centre of the 

 mass. Even the largest eggs in the ovary show the nucleus clear 

 and undivided, not the least sign of yolk-division. The oviducts are 

 thin, transparent tubes of moderate length, and considerably curved 

 or undulated, but they cannot be called convoluted. They are evi- 

 dently very capable of distension and contraction, and when not dis- 

 tended by eggs are generally strongly corrugated. They almost 



